This guide explains the five generations of multimode fiber - OM1, OM2, OM3, OM4, and OM5 - covering their physical characteristics, color coding, bandwidth, maximum distances at different data rates, optical sources (LED, VCSEL, SWDM), and real-world applications in. This guide explains the five generations of multimode fiber - OM1, OM2, OM3, OM4, and OM5 - covering their physical characteristics, color coding, bandwidth, maximum distances at different data rates, optical sources (LED, VCSEL, SWDM), and real-world applications in. Most multimode fiber types used today are OM3/OM4 and OM5, but there are still older network infrastructures, where cables inside buildings were laid a long time ago that use OM1, OM2 multimode fiber. OM1 Multimode fiber type was the first MMF version to be standardized in 1989. It has a larger. There are several kinds of multimode fiber types available for high-speed network installations, and each with a different reach and data-rate capability. With so many options, it can be tough to select the most suitable multimode fiber. This is made possible by its relatively large core diameter, typically 50 or 62. While single-mode fiber (SMF) dominates long-distance and carrier-grade infrastructure, multimode fiber remains the most cost-efficient and practical choice for enterprise buildings. For short to medium distance high speed data transport, multimode fiber optic cables are popular in data centers, enterprise networks and campus environments.